Chalk-screen for blackboard-troughs



(No Model.)

G. A. WHITE. CHALK SCREEN FOR BLAGKBOARD TROUGHS;

No. 570,692. Patented Nov. 3, 1896.

UNITED STATES PATENT OFFICE.

GEORGE A. \VHITE, OF POTSDAM, NEW YORK.

vCHALK-SCREEN FOR BLACKBOARD-TROUGHS.

SPECIFICATION forming part of Letters Patent No. 570,692, dated November 3, 1896.

Application filed June 8, 1896. Serial No. 594,749. (No model.)

To all whom it may concern.-

Be it known that I, GEORGE A. WVHITE, a citizen of the United States, residing at Potsdam, in the county of St. Lawrence, State of New York, have invented certain new and useful Improvements in Chalk-Screens for Blackboard-Troughs and the Like, of which the following is a description, reference being had to the accompanying drawings and to the letters of reference marked thereon.

My invention relates to a chalk-screen for blackboard-troughs and the like, my objectbeing to provide a simple and durable screen which can be readily attached to any trough and is so placed upon said trough that it can be readily swung out of the way for the purpose of cleaning the trough.

To this end the invention consists in the Various matters hereinafter described and claimed.

In the accompanying drawings, Figure 1 is a perspective view 'of a blackboard-trough with my improved screen attached. Fig. 2. is an end elevation thereof, and Fig. 3 is a view of the screen itself.

Referring now more particularly to the drawings, A represents a blackboard, B the trough upon the same, and O the present screen. This screen can be in one piece or in sections, as may be found most convenient, and comprises a straight flat body portion or web 0, adapted to rest over the bottom of the trough and receive the chalk, erasers, &c., and members 0 for attaching the web to the trough. In the present instance the web comprises a wire frame 0 upon which is secured a wire-netting 0 but obviously any appropriate construction of web can be employed.

To the rear side of the web screw-eyes or other members 0, for securing the screen to the trough, are attached, and, as here shown, the rear wire 0 of the frame passes through these screw-eyes. Thus the screen is attached upon the trough by simply driving or otherwise forcing the screw-eyes into the bottom thereof, or, although less desirable, the attaching members 0 can be driven into the blackboard.

It will be noticed that the screw-eyes are so located that the rear edge of the web is raised above the bottom of the trough,while the front edge falls upon the trough, and thus leaves the front wall I) of said trough projecting above the screen. By reason of this arrangement a very thin wire web can be employed, the elevation at the rear affording sufficient space between the screen and the trough-bottom for the reception of the chalk-dust and the trough the screen can be swung up entirely out of the way of the operator, while, furthermore, the screw-eyes enter the bottom of the trough and there obtain a firm hold.

From the foregoing it will be seen that the present screen is composed of but two simple parts, which are readily constructed and assembled, and that these two parts are so arranged upon the trough that ample space is provided for the dust. The screen is readily swung out of the way for the purpose of cleaning the trough, and a ledge is provided to prevent the articles upon the screen from falling off. In addition to this the screen can be applied to any trough of ordinary construction, and is attached to it in a firm and secure manner.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The combination with a blackboardtrough or the like, having a ledge, of a screen comprising a web, and securing members attached thereto at the side opposite the ledge, said securing members being also attached to the trough and the point of connection between the web and the securing members being above the body of the trough, whereby the web will be raised at one edge and at the other rest upon the trough below the ledge.

2. The combination with a blackboardtrough or the like having a ledge, of a screen comprising a web, and screw=eyes attached thereto at the side opposite the ledge, said screw-eyes being also attached to the trough th bo y of th t ugh, wher y th W Will be raised at one edge and at the other rest upon the trough below the ledge; substantially as described.

In testimony whereof I aflix my signature in presence of twowitnesses.

GEORGE A. WHITE.

Vitnesses:

T. B. SToWELL, F. H. ALLEN. 

